The present invention generally relates to a nut fastener that can be driven in only one direction.
Existing nut fasteners can be either tightened or loosened by a user. A problem with the two-way fasteners is that a person may tamper with the fastener or remove the fastener without permission. For example, if the fastener is used to seal a fluid or gas and a person, such as a child, accidentally loosens the nut fastener, the fluid or gas will be unintentionally released, creating an unsafe situation.
This invention is a novel, one-way nut fastener. The nut fastener includes a nut body with a side wall that is internally threaded and lobes that extend from the side wall of the nut body. Each lobe has a flat portion that extends substantially radially away from the side wall and a curved portion that extends from each flat portion to the flat portion of an adjacent lobe.
A special tool uses the leverage that is gained from the flat portions of the lobes to tighten the cap threads onto the threads of a stem portion. Since the leverage gained from the lobes, which is used to tighten the nut fastener, cannot be used to loosen the fastener, it is much more difficult to remove the nut fastener.